Automatic door for mines



v J. T. THOMAS. AUTOMATIC DOOR FOB MINES.

APPLICATION FILED MAIL 28,. 1921. 1,410,425 Patented Mar. 21, 1922.

2 SHEETSSHEETV l.

Patented Mar. 21, 1922.

2 SHEETS-SHEET 2.

PATENT oF ice.

JOHN T, THOMAS, OF MYERS, FLORIDA.

A'UTDlLEATIC D G int area,

Specification of Letters Patent.

on sea MINES}.

Application filed. March 28, 1921. Serial N0. 456,144.

To all whom it only concern:

Be it known that JOHN T. Ti-roiuas, a citizen of the United States of America, residing at Fort Myers, in the county of Lee and State or Florida, has invented new and useful Improvements in Automatic Doors for Mines, of which the following is a specification.

The obj ect of the invention to provide a simple and relatively inexpensive means whereby the doors in the shafts and corridors of mines may be automatically opened and closed as the cars or trains or cars traversing the tracks respectively approach and recede from the planes olthe doors; to permit of normally retaining the doors in their closed positions and of opening the same to permit of the passage of the cars without necessitating theservices oi a watchman or attendant for manipulating the doors; and with this object in view the invention consists in a construction and combination of parts of which a preferred embodiment is shown in the drawing, wherein Figure 1 is a plan view of the mine door operating mechanism applied in the opera tive position to a mine car track.

Figure 2 is a longitudinal sectional view of the same. 7

Figure 3 is a transverse section on the planeindicated by the line 3-8 of Figure 2.

Figure 4: is a detail view of one 01' the tread rockers V Figure 5 is a detail sectional view on the plane indicated by the line 5-5 of Figure'l.

Figure 6 is a detailview in perspective of one of the tread frames.

The apparatus embodies essentially the pivotal tread frames 10 arranged in operative relation. with the track rails 11 at opposite sides of the transverse plane of the door 12 which latter is preferably composed of the oppositely swinging leaves 12 and 12 arranged to overlap at their free edges to serve as means for relatively checking or limiting the closing movements thereof, said door leaves being respectively carried by hinge rods 13 which are operatively connected with tread rockers 14 disposed in the paths of downward movement of the free ends of the tread frames for actuating by the weight of cars traversing the latter.

In the construction illustrated the tread frames are mounted between the planes of the track rails and are provided with up standing lateral flanges 15 to lie at their upper edges flush with the treads of the rails when the tread frames are depressed, and to stand at an upwardly and inwardly inclined relation to and above the treads of the rails under normal conditions so that as a car or train approaches the plane of the door the movement of thewheels of the car upon the tread frame, entering the same at its pivoted end, gradually depresses the frame until the upper edges of the flanges lie flush with the treads of the track rails.

Each tread rocker consists of a transverse rock shaft 17 having arms 18 arranged in the paths of depending blocks or stirrups 19 supported by the tread. frames, and in addition said rock shaft carries a crank arm 20 connected by a rod 21 with a crank arm 22 on the main rock shaft 23 mounted transversely of the track rails beneath or adjacent to the plane of the door leaves and terminally provided with gears 2e meshing with pinions on the lower ends of the hinge rods which carry the door leaves, so that when a tread frame is depressed by the weight oi. a car traversing the same the associated rocker is actuated and communicates motion to the main rock shaft which in turn swings the door leaves in opposite directions to an open position to permit-of the passage of the car, the return of the door members to the closed position being effected by a counterbalancing weight connected by an oscillatory arm 27 with the rock shaft. Inasmuch as the cars in a mine usually are operated in trains, it is only necessary to provide that the interval between the tread :t'rames at opposite sides of the plane of the door shall be less than the length of a train in order to insure the retention ot. the door in an open position for a suilicient length of time to permit the train to pass therethrough it being obvious that the tread frame at the approach side of the door will hold the door members in an open position until the front end of the train reaches the tread frame at the opposite side of the plane of the door, and that the weight of the cars on the second-named tread frame will maintain the door members in the open position until the wheels of the last car of the train have left said frame. 7 7

As a means of retaining the door members in their open position while a car or other object traversing the track rails is passing through the door opening, and serving as a lock to guard against the closing of the door members in the event that a single car is Patented Mar. 21, 1922.,

traversing the track and thus release one tread frame before coming into engagement with the other, there 18 employed a locking mechanism consisting of a supplemental tread fram 28 arranged adjacent to one of the track rails and extending between the main tread frames 10, in the path of the flanges of wheels traversing said rail, said tread member being yieldingly held in a centrally elevated position as indicated in Figure 5, and a dog 29 for engagement with a gear or ratchet 30 carried by the rock shaft 23 and having an operating arm 31 connected by a link 32 or'the equivalent thereof with said auxiliary tread rail. As a car approaches the gate it will, as herein above described, actuate one of the tread frames 10 to open the gate and in leaving the said tread frame the wheels of the car will engage and depress the tread rail 28 to thereby throw the dog 29 into engagement with the ratchet 30 and thus lock the rock shaft against movement while the car is passing through the gate opening.

' Having described the invention, what is same in and returning the same to its normal position.

A, mine door operating apparatus having pivotally mounted door leaves, a rock shaft operatively connected with said leaves, pivotal tread frames arranged in operative relation with the track rails at opposite sides of the plane of the door, rockers disposed in the paths of movement of said tread frames and connected with said rock shaft, said door leaves being carried respectively by revoluble hinge rods geared to said rock shaft. w

3. A mine door operating apparatus having pivotally mounted door leaves, a rock shaft operatively connected with said leaves, pivotal tread frames arranged in operative relation with the track rails at opposite sides of the plane of the door, rockers disposed in the paths of movement of said tread frames and connected with said rock shaft, the said rock shaft being counterweighted to return the door leaves totheir closed position, and the latter having overlapping free edges tol form stops for limiting the closing movement thereof. V

4. A mine door operating apparatus having pivotally mounted door leaves or members, a rock shaft operatively connected with said leaves, depressible tread frames for' actuation by car Wheels traversing the track rails at opposite sides of the plane of the door and operatively connected with said rock shaft, and a door locking means consisting of a depressible tread rail the plane of which intersects the plane of thedoor, and means actuable by said rail for securing the rock shaft in its adjusted positions.

A mine door operating apparatus having pivotally mounteddoor leaves or members, a rock shaft operatively connected with said leaves, depressible treadframes for actuation by car wheels traversing the track rails at opposite sides of the plane of the door and operatively connected with said rock shaft, and a door locking means consisting of a depressible tread rail the plane of which intersects the plane of the door,

Jean '11 THOMAS,

an, i 4.1 

